Machine Kinematics

Mechanism

Question 1
Marks : +2 | -2
Pass Ratio : 100%
The inversion of a mechanism is
changing of a higher pair to a lower pair
turning its upside down
obtained by fixing different links in a kinematic chain
obtained by reversing the input and output motion
Explanation:
We can obtain as many mechanisms as the number of links in kinematic chain by fixing, in turn,different links in a kinematic chain. This method is known as inversion of the mechanism.
Question 2
Marks : +2 | -2
Pass Ratio : 100%
In a coupling rod of a locomotive, each of the four pairs is a _____________ pair.
sliding
turning
rolling
screw
Explanation:
In a locomotive, one rod of the coupling rod can only turn or revolve about a fixed axis of another rod. This takes place only in case of turning pair.
Question 3
Marks : +2 | -2
Pass Ratio : 100%
The method of obtaining different mechanisms by fixing in turn different links in a kinematic chain, is known as
structure
machine
inversion
compound mechanism
Explanation:
We can obtain as many mechanisms as the number of links in kinematic chain by fixing, in turn,different links in a kinematic chain. This method is known as inversion of the mechanism.
Question 4
Marks : +2 | -2
Pass Ratio : 100%
A type-writer constitutes a machine.
True
False
Explanation:
When a mechanism is required to transmit power or to do some particular type of work, it then becomes a machine.But in case of a typewriter there is no case of power transmission. Hence it is not a machine.
Question 5
Marks : +2 | -2
Pass Ratio : 100%
In a single slider crank chain
each of the four pairs is a turning pair
one is a turning pair and three are sliding pairs
two are turning pairs and two are sliding pairs
three are turning pairs and one is a sliding pair
Explanation:
Single slider crank chain consists of one sliding pair and three turning pairs.
Question 6
Marks : +2 | -2
Pass Ratio : 100%
The Grubler’s criterion for determining the degrees of freedom (n) of a mechanism having plane motion is
n = (l – 1) – j
n = 2(l – 1) – 2j
n = 3(l – 1) – 2j
n = 4(l – 1) – 3j
Explanation:
None
Question 7
Marks : +2 | -2
Pass Ratio : 100%
If the number of links in a mechanism are equal to l, then the number of possible inversions are equal to
l – 2
l – 1
l
l + 1
Explanation:
Whatever is the number of links in a mechanism, only that much number of inversion can be obtained.
Question 8
Marks : +2 | -2
Pass Ratio : 100%
Whitworth quick return motion mechanism is an inversion of a double slider crank chain.
True
False
Explanation:
Whitworth quick return motion mechanism is a form of single slider crank chain and it consists of one sliding pair and three turning pairs.
Question 9
Marks : +2 | -2
Pass Ratio : 100%
Whitworth quick return motion mechanism consists of three turning pairs and one sliding pair.
True
False
Explanation:
Whitworth quick return motion mechanism is a form of single slider crank chain and it consists of one sliding pair and three turning pairs.
Question 10
Marks : +2 | -2
Pass Ratio : 100%
A kinematic chain is known as a mechanism when
none of the links is fixed
one of the links is fixed
two of the links are fixed
none of the mentioned
Explanation:
When one of the links of a kinematic chain is fixed, the chain is known as mechanism.